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1.
J Environ Qual ; 49(1): 236-245, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016366

RESUMO

Antimicrobials used in livestock production can be present in manure via excretion in the feces and/or urine. Application of raw or processed (composted or stockpiled) manure to crop and pasture land as a plant nutrient source can result in antimicrobial transport to surface waters via rainfall or snowmelt runoff. Little is known regarding antimicrobial persistence in aquatic ecosystems. Consequently, dissipation of environmentally relevant concentrations of three veterinary antimicrobials (lincomycin, chlortetracycline, and sulfamethazine) was studied in three wetlands on the Canadian Prairies. Study wetlands were fortified in the fall to simulate antimicrobial transport via rainfall runoff from fall manure applications to the wetland catchments. After fortification, water column concentrations of all three antimicrobials decreased through September and October. Plotting natural logarithm values of antimicrobial concentration against time resulted in linear relationships for all three antimicrobials, indicating that the summation of all dissipation processes for each antimicrobial could be described by first-order kinetics. The slopes of the three plots were significantly different, indicating that the order of dissipation was lincomycin < sulfamethazine < chlortetracycline. Consequently, the dissipation DT50 (time required for 50% antimicrobial dissipation) values for lincomycin (14.0 d), sulfamethazine (7.0 d), and chlortetracycline (3.3 d) were significantly different. The longer DT50 values of lincomycin and sulfamethazine suggest that environmentally relevant concentrations of these antimicrobials may affect bacterial production in prairie wetlands.


Assuntos
Anti-Infecciosos , Clortetraciclina , Canadá , Ecossistema , Pradaria , Lincomicina , Sulfametazina , Áreas Alagadas
2.
J Environ Qual ; 49(3): 700-711, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016390

RESUMO

Increased phosphorus (P) availability under flooded, anaerobic conditions may accelerate P loss from soils to water bodies. Existing knowledge on P release to floodwater from flooded soils is limited to summer conditions and/or room temperatures. Spring snowmelt runoff, which occurs under cold temperatures with frequent freeze-thaw events, is the dominant mode of P loss from agricultural lands to water bodies in the Canadian Prairies. This research examined the effects of temperature on P dynamics under flooded conditions in a laboratory study using five agricultural soils from Manitoba, Canada. The treatments were (a) freezing for 1 wk at -20 °C, thawing and flooding at 4 ± 1 °C (frozen, cold); (b) flooding unfrozen soil at 4 ± 1 °C (unfrozen, cold); and (c) flooding unfrozen soil at 20 ± 2 °C (warm). Pore water and surface water were collected weekly over 8 wk and analyzed for dissolved reactive phosphorus (DRP), pH, calcium, magnesium, iron (Fe), and manganese (Mn). Soils under warm flooding showed enhanced P release with significantly higher DRP concentrations in pore and surface floodwater compared with cold flooding of frozen and unfrozen soils. The development of anaerobic conditions was slow under cold flooding with only a slight decrease in Eh, whereas under warm flooding Eh declined sharply, favoring reductive dissolution reactions releasing P, Fe, and Mn. Pore water and floodwater DRP concentrations were similar between frozen and unfrozen soil under cold flooding, suggesting that one freeze-thaw event prior to flooding had minimal effect on P release under simulated snowmelt conditions.


Assuntos
Fósforo/análise , Solo , Anaerobiose , Canadá , Congelamento , Temperatura
3.
J Environ Qual ; 49(3): 688-699, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016403

RESUMO

Ecosystem reconstruction after mining disturbance is a challenge considering the multitude of factors that affect soil formation and revegetation. In the boreal forest of western Canada, peat material is often used as the organic amendment for land reclamation to upland forest. Carbon and water dynamics of peat-dominated ecosystems differ from natural upland forest soils. The objective of this work was to evaluate the evolution of soils reconstructed after mining disturbance using 13 C and 2 H analyses of n-alkane tracers. Ten soils from natural ecosystems were sampled (0-10 cm) and compared with 11 soils from novel ecosystems ranging in age from 0 to 30 yr, as well as a fresh peat sample. Soils supported different vegetation, including pine (Pinus spp.), aspen (Populus spp.), and white spruce [Picea glauca (Moench) Voss]. Despite overlaps for some individual n-alkanes, we found a dominance of n-C25 in reconstructed soils, also dominant in the peat material, and a dominance of n-C27 in natural soils, one of the dominant n-alkanes in natural forest vegetation. In addition, there was a significant difference in odd n-alkane δ2 H and δ13 C values between natural and reconstructed soils (p < .05). Differences in δ2 H values, more negative for reconstructed soils than for natural soils, were attributed to changes in soil moisture, from wetter peat-dominated soils to drier upland forests; among forest types, δ2 H values were most negative under pine vegetation. The δ13 C composition of odd n-alkanes, in particular n-C27 , was significantly related to tree age (p < .05). Overall, both 2 H and 13 C isotopic signatures of odd n-alkanes exhibited differences between natural and reconstructed soils. However, within the reconstructed soils, neither isotopic signature showed a clear evolution with age since reclamation.


Assuntos
Carbono , Solo , Alcanos , Canadá , Ecossistema , Hidrogênio , Isótopos
4.
J Environ Qual ; 49(5): 1435-1444, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016451

RESUMO

Chlortetracycline (CTC), an antimicrobial administered as a feed additive to cattle, swine, and poultry, is present in the corresponding manure. Land application of raw or processed (composted or stockpiled) manure provides a mechanism by which CTC (and other antimicrobials) enters the environment and becomes available for transport to surface receiving waters via rainfall or snowmelt runoff. Chlortetracycline has been detected in Canadian surface waters, but little has been reported on its fate in aquatic ecosystems. To address this knowledge gap, the dissipation of CTC-enol was monitored in deionized water and water typical of wetlands within the prairie region of Canada. In deionized water, CTC-enol tautomerized to CTC-keto, and both tautomers epimerized to 4-epi-CTC-enol and 4-epi-CTC-keto, respectively. Irreversible isomerization to iso-CTC occurred, which then epimerized to 4-epi-iso-CTC. In wetland water, although tauterization of CTC-enol to CTC-keto occurred, there was no evidence of the formation of the 4-epimers of either CTC-enol or CTC-keto. The major product formed in the wetland water was iso-CTC, some of which epimerized to 4-epi-iso-CTC. Although CTC-enol was shown to tautomerize to CTC-keto, the concentration of CTC-keto remained low in both deionized and wetland water, suggesting that the isomerization of CTC-enol to iso-CTC most likely occurred via CTC-keto. The dissipation of CTC-enol in wetland water was described by pseudo first-order kinetics with a DT50 (time required for 50% dissipation) value of 4.8 h. The short DT50 value of CTC and reduced antimicrobial activity of iso-CTC and 4-epi-iso-CTC suggest a lower probability for selection for CTC-resistant bacteria in Canadian Prairie aquatic ecosystems.


Assuntos
Clortetraciclina , Animais , Canadá , Bovinos , Ecossistema , Pradaria , Isomerismo , Suínos , Áreas Alagadas
5.
J Environ Qual ; 49(4): 882-895, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33016498

RESUMO

Farmers, food supply companies, and policymakers need practical yet scientifically robust methods to quantify how improved nitrogen (N) fertilizer management can reduce nitrous oxide (N2 O) emissions. To meet this need, we developed an empirical model based on published field data for predicting N2 O emission from rainfed maize (Zea mays L.) fields managed with inorganic N fertilizer in the United States and Canada. Nitrous oxide emissions ranged widely on an area basis (0.03-32.9 kg N ha-1 yr-1 ) and a yield-scaled basis (0.006-4.8 kg N Mg-1 grain yr-1 ). We evaluated multiple modeling approaches and variables using three metrics of model fit (Akaike information criteria corrected for small sample sizes [AICc], RMSE, and R2 ). Our model explains 32.8% of the total observed variation and 50% of observed site-level variation. Soil clay content was very important for predicting N2 O emission and predicting the change in N2 O emission due to a change in N balance, with the addition of a clay fixed effect explaining 37% of site-level variation. Sites with higher clay content showed greater reductions in N2 O emission for a given reduction in N balance. Therefore, high-clay sites are particularly important targets for reducing N2 O emissions. Our linear mixed model is more suitable for predicting the effect of improved N management on N2 O emission in maize fields than other published models because it (a) requires only input data readily available on working farms, (b) is derived from field observations, (c) correctly represents differences among sites using a mixed modeling approach, and (d) includes soil texture because it strongly influences N2 O emissions.


Assuntos
Gases de Efeito Estufa , Zea mays , Agricultura , Canadá , Nitrogênio , Estados Unidos
6.
Can J Surg ; 63(5): E393-E394, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33009900

RESUMO

SUMMARY: The impact of waiting for surgery on the mental health of patients usually receives little attention. Because of the coronavirus disease 2019 (COVID-19) pandemic, the waits for elective surgery have been lengthening, potentially inducing or exacerbating mental health burdens. Provinces' health systems need to provide better support to assess not only patients' physical health, but also their mental health, and provide them with timely access to care based on need. A stepped care approach is needed to mitigate negative mental health effects associated with prolonged waits for elective operations. To provide the best care possible, we need to recognize and address both the physical and mental health problems of our waiting patients.


Assuntos
Infecções por Coronavirus/prevenção & controle , Procedimentos Cirúrgicos Eletivos/psicologia , Controle de Infecções/normas , Saúde Mental , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Cuidados Pré-Operatórios/métodos , Betacoronavirus/patogenicidade , Canadá/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Procedimentos Cirúrgicos Eletivos/normas , Acesso aos Serviços de Saúde/normas , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Fatores de Tempo , Tempo para o Tratamento , Listas de Espera
7.
Can J Surg ; 63(5): E418-E421, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33009901

RESUMO

SUMMARY: The Canadian Network for International Surgery (CNIS) hosted a workshop in May of 2020 with a goal of critically evaluating Trauma Team Training courses. The workshop was held virtually because of the coronavirus disease 2019 (COVID-19) pandemic. Twenty-three participants attended from 8 countries: Canada, Guyana, Kenya, Nigeria, Switzerland, Tanzania, Uganda and the United States. More participants were able to attend the virtual meeting than the traditional in-person meetings. Web-based videoconference software was used, participants presented prerecorded PowerPoint videos, and questions were raised using a written chat. The review proved successful, with discussions and recommendations for improvements surrounding course quality, lecture content, skills sessions, curriculum variations and clinical practical scenarios. The CNIS's successful experience conducting an online curriculum review involving international participants may prove useful to others proceeding with collaborative projects during the COVID-19 pandemic.


Assuntos
Congressos como Assunto/organização & administração , Infecções por Coronavirus/prevenção & controle , Currículo , Cirurgia Geral/educação , Cooperação Internacional , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus/patogenicidade , Canadá/epidemiologia , Congressos como Assunto/normas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Cirurgia Geral/métodos , Guiana/epidemiologia , Humanos , Controle de Infecções/organização & administração , Controle de Infecções/normas , Quênia/epidemiologia , Nigéria/epidemiologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Suíça/epidemiologia , Tanzânia/epidemiologia , Uganda/epidemiologia , Estados Unidos/epidemiologia , Comunicação por Videoconferência/organização & administração , Comunicação por Videoconferência/normas , Ferimentos e Lesões/cirurgia
8.
PLoS One ; 15(9): e0239253, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946479

RESUMO

PURPOSE: To examine the psychological impact of fertility treatment suspensions resulting from the COVID-19 pandemic and to clarify psychosocial predictors of better or worse mental health. METHODS: 92 women from Canada and the United States (ages 20-45 years) whose fertility treatments had been cancelled were recruited via social media. Participants completed a battery of questionnaires assessing depressive symptoms, perceived mental health impact, and change in quality of life related to treatment suspensions. Potential predictors of psychological outcomes were also examined, including several personality traits, aspects of social support, illness cognitions, and coping strategies. RESULTS: 52% of respondents endorsed clinical levels of depressive symptoms. On a 7-point scale, participants endorsed a significant decline in overall quality of life (M(SD) = -1.3(1.3), p < .0001) as well as a significant decline in mental health related to treatment suspensions on a scale from -5 to +5 (M(SD) = -2.1(2.1), p < .001). Several psychosocial variables were found to positively influence these outcomes: lower levels of defensive pessimism (r = -.25, p < .05), greater infertility acceptance (r = .51, p < .0001), better quality social support (r = .31, p < .01), more social support seeking (r = .35, p < .001) and less avoidance of infertility reminders (r = -.23, p = .029). CONCLUSION: Fertility treatment suspensions have had a considerable negative impact on women's mental health and quality of life. However, these findings point to several protective psychosocial factors that can be fostered in the future to help women cope.


Assuntos
Betacoronavirus , Infecções por Coronavirus/psicologia , Infertilidade/tratamento farmacológico , Pneumonia Viral/psicologia , Suspensão de Tratamento , Adulto , Canadá/epidemiologia , Feminino , Fármacos para a Fertilidade Feminina/provisão & distribução , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Infertilidade/psicologia , Saúde Mental , Pessoa de Meia-Idade , Pandemias , Qualidade de Vida/psicologia , Inquéritos e Questionários , Estados Unidos/epidemiologia , Adulto Jovem
11.
Value Health ; 23(9): 1137-1141, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32940230

RESUMO

OBJECTIVES: Hepatitis C virus (HCV) antivirals have been shown to be highly effective with minimal adverse effects, but they are costly. Little is known about the national spending on this drug class in either Canada or the United States, 2 countries with different drug pricing regulations. Thus the objective of this study was to compare drug expenditure on HCV medications in the United States and Canada. METHODS: This was a retrospective cross-sectional study using the IQVIA National Sales Perspectives (United States) and Geographic Prescription Monitor (Canada) databases, which contains prescription transactions from American and Canadian pharmacies. All prescription claims for the period between January 1, 2014, and June 30, 2018, were used to describe HCV antiviral expenditure in both countries. RESULTS: The United States and Canada spent $59.7 billion and $2.8 billion on HCV medications, respectively. Population-adjusted HCV medication costs were higher in the United States ($1 million per 100 000 population) compared with Canada ($0.4 million per 100 000 population). CONCLUSIONS: Although the rates of HCV infection are similar in the 2 countries, these findings highlight the differences in both the reimbursement utilization policy for HCV treatments in the countries and the major differences in drug pricing policies. As policies to reduce drug spending in the United States are explored, this article highlights the potential cost implications of implementing Canadian index pricing.


Assuntos
Antivirais/economia , Custos de Medicamentos/estatística & dados numéricos , Hepatite C/tratamento farmacológico , Canadá , Estudos Transversais , Política de Saúde , Humanos , Estudos Retrospectivos , Estados Unidos
12.
Value Health ; 23(9): 1157-1162, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32940233

RESUMO

OBJECTIVES: Despite wide support for patient involvement in health technology assessments (HTA), determining meaningful engagement is complex. This article explores experiences and perceptions among patient groups participating in the Canadian Agency for Drugs and Technologies in Health (CADTH)'s pan-Canadian Oncology Drug Review (pCODR) process. METHODS: We created a qualitative interview study comprising 22 semi-structured telephone interviews with individuals representing 21 different patient groups registered with the pCODR process. The analysis used a qualitative descriptive approach employing techniques from grounded theory. RESULTS: Patient groups view the ability to make submissions to the pCODR process as a meaningful activity closely aligned with organizational priorities. Concurrently, they face substantial resource challenges to prepare submissions, including high opportunity costs and difficulty accessing needed literature and finding relevant patients. Although patient groups felt that CADTH is committed to transparency, they expressed considerable uncertainty around the direct impact of their submissions and desired additional avenues for engagement. CONCLUSIONS: This study suggests a strong commitment by patient groups to participate in the pCODR process despite uncertainty about how their submissions are used to inform HTA recommendations. Identifying opportunities to provide both financial and nonfinancial resources to patient groups is crucial to encouraging and supporting their meaningful participation in HTA processes.


Assuntos
Antineoplásicos/economia , Oncologia/economia , Participação do Paciente , Avaliação da Tecnologia Biomédica/organização & administração , Canadá , Análise Custo-Benefício , Tomada de Decisões , Humanos , Pesquisa Qualitativa
13.
Environ Monit Assess ; 192(9): 614, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32875389

RESUMO

This review identifies strengths and weaknesses of water monitoring programs selected by Canadian water managers. We used 22 criteria, guided by outcomes of an exploratory study and supported by 21 semi-structured key informant interviews. The highest-scoring programs include the Slave Watershed Environmental Effects Program (Canada), the Government of Canada's Environmental Effects Monitoring Program, and Healthy Land and Water (Australia). We describe five recommendations for improving future freshwater monitoring frameworks: (1) recognize different knowledge approaches (especially Indigenous), (2) use multiple reporting formats, (3) clarify monitoring and management roles, (4) apply a whole-watershed approach, and (5) link monitoring to management and decision-making.


Assuntos
Monitoramento Ambiental , Água Doce , Austrália , Canadá
14.
Environ Monit Assess ; 192(9): 613, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32875407

RESUMO

Many environmental monitoring programs include an assessment of the health of fish populations using a sentinel species and include an indicator of reproductive potential. Knowledge of the reproductive strategy of the fish species is critical for data interpretation but is not always known. The reproductive strategy of a species can be determined from detailed histological analyses of ovaries throughout the reproductive cycle; however, these studies can be costly and can delay the implementation of a monitoring program. Three quick and cost-effective methods of predicting the reproductive strategy (annual single spawning or annual multiple spawning) are evaluated in this study using predicted probabilities from binary logistic regression models as a means of classifying the reproductive strategies of 18 different fish species in Atlantic Canada. The first method was based on the hypothesis that the variability in the ovary weight-body weight relationship in prespawning females is higher in multiple spawners. This method did not have a good classification rate due to some multiple spawners having low variability. The other two methods involved predictor variables representing the proportion of oocytes in different stages of development and predictor variables representing the distribution of oocyte sizes during the prespawning season for 111 fish (25 different samples for species). Predicted probabilities from these regression models could be used to correctly classify the reproductive strategies of all 25 samples (development stage model) and all but one sample (oocyte size distribution model). These models can be used to estimate the reproductive strategy of a species from a single sample of fish collected during the prespawning period to support species selection and data interpretation in environmental monitoring programs.


Assuntos
Monitoramento Ambiental , Reprodução , Animais , Canadá , Feminino , Peixes , Ovário
17.
F1000Res ; 92020.
Artigo em Inglês | MEDLINE | ID: mdl-32983415

RESUMO

Launched in 2000 and held every year since, the Bioinformatics Open Source Conference (BOSC) is a volunteer-run meeting coordinated by the Open Bioinformatics Foundation (OBF) that covers open source software development and open science in bioinformatics. Most years, BOSC has been part of the Intelligent Systems for Molecular Biology (ISMB) conference, but in 2018, and again in 2020, BOSC partnered with the Galaxy Community Conference (GCC). This year's combined BOSC + GCC conference was called the Bioinformatics Community Conference (BCC2020, bcc2020.github.io). Originally slated to take place in Toronto, Canada, BCC2020 was moved online due to COVID-19. The meeting started with a wide array of training sessions; continued with a main program of keynote presentations, talks, posters, Birds of a Feather, and more; and ended with four days of collaboration (CoFest). Efforts to make the meeting accessible and inclusive included very low registration fees, talks presented twice a day, and closed captioning for all videos. More than 800 people from 61 countries registered for at least one part of the meeting, which was held mostly in the Remo.co video-conferencing platform.


Assuntos
Biologia Computacional , Congressos como Assunto , Canadá , Humanos
19.
Artigo em Inglês | MEDLINE | ID: mdl-32987764

RESUMO

Background: This cross-sectional online survey investigates the prevalence of obsessive-compulsive disorder (OCD) symptoms at an early stage of the COVID-19 pandemic in Canada. Methods: OCD symptoms, moderate/high stress, likely generalized anxiety disorder (GAD) and likely major depressive disorder (MDD) were assessed with the Brief Obsessive-Compulsive Scale (BOCS), Perceived Stress Scale (PSS), Generalized Anxiety Disorder 7-item (GAD-7) scale, and Patient Health Questionnaire-9 (PHQ-9) scale, respectively. Results: Out of 32,805 individuals subscribed to Text4Hope, 6041 completed an online survey; the response rate was 18.4%. Overall, 60.3% of respondents reported onset of OCD symptoms and 53.8% had compulsions to wash hands during the COVID-19 pandemic. Respondents who showed OCD symptoms only since the start of COVID-19 were significantly more likely to have moderate/high stress (z = 6.4, p < 0.001), likely GAD (z = 6.0, p < 0.001), and likely MDD (z = 2.7, p < 0.01). Similarly, respondents who engaged in compulsive hand washing were significantly more likely to have moderate/high stress (z = 4.6, p < 0.001) and likely GAD (z = 4.6 p < 0.001), but not likely MDD (z = 1.4, p = 0.16). Conclusion: The prevalence of OCD symptoms increased during the COVID-19 pandemic, at a rate significantly higher than pre-pandemic rates reported for the sample population. Presenting with OCD symptoms increased the likelihood of presenting with elevated stress, likely GAD, and likely MDD.


Assuntos
Transtornos de Ansiedade/epidemiologia , Infecções por Coronavirus/psicologia , Transtorno Depressivo Maior/epidemiologia , Saúde Mental , Transtorno Obsessivo-Compulsivo/epidemiologia , Pneumonia Viral/psicologia , Betacoronavirus , Canadá/epidemiologia , Estudos Transversais , Humanos , Pandemias , Prevalência , Estresse Psicológico/epidemiologia
20.
J Am Med Dir Assoc ; 21(10): 1365-1370.e7, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32981662

RESUMO

During the first few months of the coronavirus disease 2019 (COVID-19) pandemic, Canadian nursing homes implemented strict no-visitor policies to reduce the risk of introducing COVID-19 in these settings. There are now growing concerns that the risks associated with restricted access to family caregivers and visitors have started to outweigh the potential benefits associated with preventing COVID-19 infections. Many residents have sustained severe and potentially irreversible physical, functional, cognitive, and mental health declines. As Canada emerges from its first wave of the pandemic, nursing homes across the country have cautiously started to reopen these settings, yet there is broad criticism that emerging visitor policies are overly restrictive, inequitable, and potentially harmful. We reviewed the nursing home visitor policies for Canada's 10 provinces and 3 territories as well as international policies and reports on the topic to develop 10 provi-informed, data-driven, and expert-reviewed guidance for the re-opening of Canadian nursing homes to family caregivers and visitors.


Assuntos
Infecções por Coronavirus/prevenção & controle , Solidão/psicologia , Casas de Saúde/organização & administração , Pandemias/prevenção & controle , Segurança do Paciente/normas , Pneumonia Viral/prevenção & controle , Isolamento Social/psicologia , Envelhecimento/psicologia , Betacoronavirus , Canadá , Infecções por Coronavirus/epidemiologia , Gerenciamento Clínico , Política de Saúde , Humanos , Pneumonia Viral/epidemiologia
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